Silicon nanowire (SiNW) arrays were fabricated from a nanosphere lithography patterned gold mask by metal-assisted chemical etching. The optical reflectance of these SiNW arrays was studied as a function of nanowire diameter, pitch, and height. Less than 1% reflectance was achieved over the 300 to 1000 nm wavelength range for both 200 nm and 300 nm diameter wire arrays at different pitches and at as low as 3 m wire heights. With these SiNW arrays, a monolayer doping process was used to generate a radial p-n junction inside the nanowires, enabling the fabricated of silicon nanowire solar cells. Slight rectification and light- generated current was measured in short (1.6 µm) nanowire devices, however, the observed behavior was not what was expected of a typical p-n junction diode. It was hypothesized that lack of surface passivation led to surface charge depletion along the nanowire sidewalls, which ultimately led to poor device performance. This work presents the demonstration, characterization and implementation of a full device fabrication process for generating silicon nanowires via nanosphere lithography and metal- assisted chemical etching to pave the way for future work exploring silicon nanowire devices at RIT.
Soule, Cody W.
"Silicon Nanowire Solar Cells by Metal-Assisted Chemical Etching,"
Journal of the Microelectronic Engineering Conference: Vol. 24:
1, Article 42.
Available at: https://repository.rit.edu/ritamec/vol24/iss1/42